Comparative Studies of Two Types of Viscous Damage Models for Concrete Under Dynamic Loading

Abstract:

In order to reflect the rate dependence of mechanical behavior under dynamic loading， based on the elastoplastic damage theory framework， the dynamic damage evolution is expanded from the static model. The damage evolution is delayed due to the rate effect， which leads to the strengthening phenomena. Inspired by the viscoplastic theory， two types of dynamic visco-damage evolution models are established in the damage subspace： Perzyna model and Duvaut-Lions model. The constitutive theories and the numerical results of the two kinds of viscous damage evolution models are compared respectively. In terms of constitutive theory， the two models have different viscous variables. In the simulation results， concrete dynamic behaviors simulated by the linear visco-damage models with Perzyna format and Duvaut-Lions format are nearly consistent. In contrast， those calculated by the nonlinear visco-damage models with Perzyna format and Duvaut-Lions format differ. In addition， the improvement in dynamic strength predicted by both nonlinear models agrees well with test data， indicating that both can reflect the rate sensitivity of concrete material.